This invention relates to a builder machanism for textile machines. More particularly, it relates to an improved, extremely compact builder mechanism of the electromechanical type which controls the extents of reciprocatory vertical movements of machine elements which layer fibrous strands onto cops, such as the movements of ring rails in spinning machines or the movements of roving spindles in speed frames. The present builder includes an electromechanical control means concentric to a builder shaft which is interconnected with a reversible drive means for the aforesaid machine elements, the present control means including a differential gearing assembly which effects with time of machine operation incremental angular advancements of switch components interconnected with the drive means to effect reversals by means of pick gear and pick gear pawl members also disposed concentric to the builder shaft's axis. By such concentric construction, the present builder is extremely compact and imparts the advantage of being installed or removed from the builder shaft as a unit for maintenance in extremely short time intervals with concomitant economic benefits of reducing unproductive intervals of machine downtime for such maintenance.
In contast, mechanical builder mechanisms conventionally employed effect control over the change in reversals of reciprocatory elements of most ring spinning or roving machines through the use of a builder cam interconnected by mechanical elements to the builder shaft to effect required stepped advancements of the points of reciprocatory reversals in vertical movement of the strand layering elements. Typical of such prior art constructions are the builders shown, for example, in U.S. Pats. Nos. 678,408; 2,982,487; 3,072,350; 3,325,109; and 3,369,764.
Attempts have been made to move away from the all mechanical type builder mechanisms in order to provide certain advantages. Among these are the electromechanical builder mechanisms which possess the potential to provide a more instantaneous control response in the patterning of reciprocatory stroke reversals than the all mechanical systems, thus to hold forth the promise of providing a more precise patterning of strand layers on a cop than mechanical mechanisms which are limited in this regard because of time lags induced in the transmission of movement by multiple mechanical linkages. Typical ones of proposed electromechanical builders are disclosed by U.S. Pats. Nos. 3,097,475; 3,367,588; 3,461,747; 3,477,654; 3,484,050; and 3,547,363.
In such prior art mechanical and electromechanical builder mechanisms it is to be readily noted that their components are fixed to and distributed among a plurality of shafts or other supporting elements which are spaced apart or otherwise physically disassociated from one another. Such arrangements can provide disadvantages and problems in that various components may be located where they may, for example, be exposed to unauthorized tampering and/or to damage, as from accidental impacts, lint accumulations, and the like. Additionally, such arrangements may impede an operator's ready access for adjustment of certain components which normally must be adjusted when it is desired to change the configuration or "build" of the strand packages to be produced. Further and perhaps most importantly, such arrangements tend to provide extended machine downtimes for maintenance work which would be required, such as to remedy malfunctions of the builder mechanism especially when occurring for some unapparent and not immediately ascertainable reason. Thus, with prior art arrangements the textile machine may remain idle while each of the various control components of the builder mechanism is individually removed and examined to locate the source of malfunction, and until the malfunctioning component is identified and replaced. Such idle intervals may be of several hours to several days in duration because of the difficulties involved in removing the separated components, their examination and replacement. This has imposed substantial economic disadvantages by removing the machine from production for these prolonged intervals. A yet further economic disadvantage present in prior art constructions resides in the requirement for substantial space to house these builder mechanisms with their dispersed components. With the ever increasing rise in costs of already expensive floor space in commercial textile mills, the economic disadvantages inherent in such prior art mechanisms are manifest.